This is an awesome idea!

Like, your infamy or virtue(?) precedes you. If for example, your this holy devout person, some members of the bandit gang when confronting you may lay down their arms and refuse to fight you. Or maybe even fight their own kind.
Maybe an option to negotiate with them if your really . They could somehow randomly appear in fights where your health is low to help you. (much like that perk in Fallout 3, Mysterious Stranger I think?)

Or if your this "holy crap its THE GUNSLINGER!" they would just run away or push someone else into your line of attack as a diversion and leg it.
Also the opposite of the negotiation option, you could maybe convince some of them to fight themselves by offering a share of the loot, spreading chaos in their ranks.

Like I said, love the idea and its implications